History BewareTheNiceOnes / LiveActionTV

* Most, if not all, PowerRangers fit into this trope, with a special emphasis on the female rangers, but the MostTriumphantExample would have to be Kimberly. A tiny wisp of a creature who doesn't appear to weigh 100 pounds, she acts like a 80s ValleyGirl more times than not, but when threatened she becomes one of the toughest rangers ever. Made even more obvious with her weapon, The Power Bow. Her arrows have been shown to be able to turn corners and navigate through trees, meaning she has what amounts to a portable rocket launcher at her disposal.

* Just about everyone who encounters [[TheSarahConnorChronicles the Connors]] ends up thinking that [[RobotGirl Cameron]] is an odd but otherwise docile girl. And she stays that way, unless [[TranquilFury someone threatens the Connors.]]
* Leo of {{Charmed}}, he is a peaceful healer who often gives words of advice to the Charmed Ones. But people forget that he was a medic during World War II and if anyone threatens Piper or his sons, he will kill.

** An ever better example his is RAAAAAAAAAAAAAAAAGE when [[spoiler: Wild Bill Hicock, Bullock's new friend, is shot and killed by a cowardly poker player]] Bullock comes thisclose to choking the man to death while he's imprisoned, then, when the killer is turned loose due to Deadwood's status as an Annexe, he flies into another of his barely contained rages and goes after him on horseback. It's only his annoying habit of being an honourable man that forces him to take the man to a 'proper' town to have justice served and not just barehanded murder him himself
*** Yet another example is his very first appearance as an apparently quite amiable sheriff, willing to listen to a horse thief, who shot Bullock, in his attempt to bribe Bullock into releasing him. When a Lynch mob turn up to get the guy, Bullock fends them off without raising his gun and offers mercy tot he man by...hanging him a few hours early, having to jerk the man off a stool so his neck breaks-but his death is legal.
**** Then there's the fact [[spoiler:he might be a quicker draw than Wild Bill-in the pilot a shifty cowpoke tells the story of a family massacred out on the road. Bullock, Bill and a few others, ride out and end up rescuing a small girl. When they return, the cowpoke is now even shiftier(it later turns out he and his brother where behind the massacre) and Bullock and Wild Bill see fit to shoot him down. Bill has to ask if Bullock shot first even though they seemed to draw at the same time. While Bullock declares it was Bill who shot first, it's strongly implied Bullock is the quicker draw(though to be fair, by this point, Bill is older and drunker than he was in his heyday]]

** Let's not forget about Hawkeye, normally a nice guy with a penchant for pulling pranks. However, if he finds out you are causing harm to children, he doesn't care if you are in the army as well- you are going to get it.
* Juliet in ''{{Lost}}'' also qualifies. As seen in her flashbacks, she used to be an incredibly mousy and docile person, frequently letting people (especially her ex-husband) walk all over her but all of that changed [[BreakTheCutie when she got to the island and met Ben Linus, who extended her six-month stay there to eternity]]. Since then and especially after discovering [[spoiler: Ben's many other lies to her, including his involvement in her lover's death]] she [[TookALevelInBadass took several levels in badass]]. The biggest evidence of the damage done to her comes in Season 5, [[spoiler: when Sawyer's throwaway look at Kate turns out to be the last straw and Juliet decides that the only response she can muster is to detonate a hydrogen bomb]]

* Blair Sandburg in ''TheSentinel.'' Anthropology grad student, raised by a mother who could be described as "the last flower child not gone to seed"--but threaten or even worse ''hurt'' Jim and you'll wish you had left matters well enough alone.

* Most, if not all, PowerRangers fit into this trope, with a special emphasis on the female rangers, but the MostTriumphantExample would have to be Kimberly. A tiny wisp of a creature who doesn't appear to weight 100 pounds, she acts like a 80's valley girl more times than not, but when threatened she becomes one of the toughest rangers ever. Made even more obvious with her weapon, The Power Bow. Her arrows have been shown to be able to turn corners and navigate through trees, meaning she has what amounts to a portable rocket launcher at her disposal.

*** "Although I thought I might just shoot you in the throat instead. Now, if I pierce one of your carotid arteries, considering the temperature in here, 'cause I think somebody shot the thermostat, the blood loss is gonna be heavy. And there's a chance I'll puncture a vocal cord and you won't even be able to scream. But you'll want to when the blood loss to your brain results in a cerebral vascular event. That's a stroke. I wasn't trying to sound snooty." The one and only, [[OnmindisciplinaryScientist Winnifred Burkle]].

** Giles. Quiet, stuttering, somewhat bumbling Giles, efficiently beats the crap out of [[spoiler: Ethan Rayne]], then kicks him to get information. He goes after [[spoiler: Angel]] with a flaming bat. He stabs [[spoiler: the mayor]] in the chest with a sword. He delays Buffy so [[spoiler: Principal Wood]] can beat [[spoiler: Spike]] to death with his bare hands. But he really proves it in season five. First, when a recalcitrant servant of the BigBad refuses to talk, he tells the girls to get some rope; the camera follows them and we hear a noise; whip pan back to a now very talkative demon. And in the season finale, when he [[spoiler: suffocates innocent and long suffering Ben in order to kill Glory.]]

*** Eleven have made the villains scatter ''twice'', just by telling them to remember who he is. [[spoiler: though the second time didn't really go as planned.]]

** The Eleventh Doctor is usually a friendly, happy go lucky guy who likes fish fingers with custard and {{Nice Hat}}s. But when the Weeping Angels mocked him and killed a perfectly innocent man, he gave a BadassBoast, and then proceeded to ''erase them from time''.

* Eric Gotts from ''{{Wonderfalls}}'' was by far the nicest, least obnoxious and least ridiculous of the main characters, but when his cheating ex-wife turned up, he was downright vicious to her, including throwing a glass across the room, narrowly missing her head.

*** "Although I thought I might just shoot you in the throat instead. Now, if I pierce one of your carotid arteries, considering the temperature in here, 'cause I think somebody shot the thermostat, the blood loss is gonna be heavy. And there's a chance I'll puncture a vocal cord and you won't even be able to scream. But you'll want to when the blood loss to your brain results in a cerebral vascular event. That's a stroke. I wasn't trying to sound snooty." The one and only, Winnifred Burkle.

*** And in the hell dimension in which she was trapped for five years, the cave she hid out in had a handy nearby ravine that she used to dispose of bodies.

* The eponymous {{Merlin}}. Adorable, loyal, and a bit of a Dojikko, but God help you if you ever try to kill anyone he cares about, because that is last thing you will ever do. His anger is sudden and his powers are fierce and he ''will'' blast you off the face of the Earth.

** Let's not forget about Hawkeye, while normally a nice guy with a penchant for pulling pranks. However if he finds out someone is causing harm to children; he doesn't care if you are in the army as well you are going to get it.

* Let's not forget about Hawkeye, while normally a nice guy with a penchant for pulling pranks. However if he finds out someone is causing harm to children; he doesn't care if you are in the army as well you are going to get it.

* Doctor Parker, from FlandersCompany, is a very nice fellow, always calm and collected, happy to help his company and others in general... [[spoiler:Until his SuperPoweredEvilSide takes control. Expect a lot of slaughters and massive quantity of blood.]]

** Another Doctor companion: River Song. River and the Doctor have a very flirty, teasing relationship. Her calling card is "Hello, sweetie!" and she enjoys crooking her finger to make the Doctor come running. However, when a [[spoiler:Dalek shot the Doctor in The Big Bang]], not only did she kill it, she stared it down, told it she knew its weaknesses, told it exactly how she was going to kill it ([[spoiler:by shooting it THROUGH THE EYE!!!]]) and forced it to beg for mercy ''three times'' before finally blowing it away.
--->'''River:''' I'm River Song. ''[[BadassBoast Check your records again.]]''

** Not to mention Delenn, the generally mild-mannered Minbari ambassador from the religion caste, whose mentor once said: "If you want to make a point, why not make it [[ThereIsNoKillLikeOverkill so that no-one misses it?]]". She took it to heart.

** Another Doctor companion, River Song. River and the Doctor have a very flirty, teasing relationship. However, when a [[spoiler:Dalek shot the Doctor in The Big Bang]], not only did she kill it, she stared it down, told it she knew its weaknesses, told it exactly how she was going to kill it,[[spoiler:by shooting it THROUGH THE EYE!!!]], and forced it to beg for mercy THREE times before finally blowing it away.

** The Eleventh Doctor is usually a friendly, happy go lucky guy. But when the Weeping Angels mocked him and killed a perfectly innocent man, he gave a BadassBoast, and then proceeded to ''erase them from time''.

*** This is one of the Doctor's most {{Badass}} scenes. Saying "look me up" in a library really gets into the over-the-top coast.